The present invention relates to an electric machine with a coil body and a multi-turn winding wound on the coil body. In particular, the present invention relates to a transverse flux machine or a cylindrical linear motor.
The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention.
When coils for electromagnets are manufactured, a wire is usually wound helically in one layer and spirally above one another in a plurality of layers. This results in empty spaces in the regions of the bottom and top layers and at the sides of the windings. The empty spaces result in reduced thermal conductivity and therefore to a lower power efficiency of the system operated with the electromagnet, e.g. a cylindrical linear motor. High utilization is particularly important with electromagnetic direct drives having low field speeds in order to keep costs low. Consequently, attempts are being made to achieve the highest possible slot fill factor.
With known winding methods, which produce spiral or helical windings, higher thermal resistances resulting from the empty spaces are generally accepted. No solutions for reducing the thermal resistance have been implemented to date.
It would therefore be desirable and advantageous to provide an improved winding structure for an electric machine, which obviates prior art shortcomings and is able to specifically increase the efficiency of the electric machine which can be used in a direct drive or braking system.